.. _mgr-cephadm-monitoring: Monitoring Services =================== Ceph Dashboard uses `Prometheus `_, `Grafana `_, and related tools to store and visualize detailed metrics on cluster utilization and performance. Ceph users have three options: #. Have cephadm deploy and configure these services. This is the default when bootstrapping a new cluster unless the ``--skip-monitoring-stack`` option is used. #. Deploy and configure these services manually. This is recommended for users with existing prometheus services in their environment (and in cases where Ceph is running in Kubernetes with Rook). #. Skip the monitoring stack completely. Some Ceph dashboard graphs will not be available. The monitoring stack consists of `Prometheus `_, Prometheus exporters (:ref:`mgr-prometheus`, `Node exporter `_), `Prometheus Alert Manager `_ and `Grafana `_. .. note:: Prometheus' security model presumes that untrusted users have access to the Prometheus HTTP endpoint and logs. Untrusted users have access to all the (meta)data Prometheus collects that is contained in the database, plus a variety of operational and debugging information. However, Prometheus' HTTP API is limited to read-only operations. Configurations can *not* be changed using the API and secrets are not exposed. Moreover, Prometheus has some built-in measures to mitigate the impact of denial of service attacks. Please see `Prometheus' Security model ` for more detailed information. Deploying monitoring with cephadm --------------------------------- By default, bootstrap will deploy a basic monitoring stack. If you did not do this (by passing ``--skip-monitoring-stack``, or if you converted an existing cluster to cephadm management, you can set up monitoring by following the steps below. #. Enable the prometheus module in the ceph-mgr daemon. This exposes the internal Ceph metrics so that prometheus can scrape them. .. code-block:: bash ceph mgr module enable prometheus #. Deploy a node-exporter service on every node of the cluster. The node-exporter provides host-level metrics like CPU and memory utilization. .. code-block:: bash ceph orch apply node-exporter '*' #. Deploy alertmanager .. code-block:: bash ceph orch apply alertmanager 1 #. Deploy prometheus. A single prometheus instance is sufficient, but for HA you may want to deploy two. .. code-block:: bash ceph orch apply prometheus 1 # or 2 #. Deploy grafana .. code-block:: bash ceph orch apply grafana 1 Cephadm takes care of the configuration of Prometheus, Grafana, and Alertmanager automatically. However, there is one exception to this rule. In a some setups, the Dashboard user's browser might not be able to access the Grafana URL configured in Ceph Dashboard. One such scenario is when the cluster and the accessing user are each in a different DNS zone. For this case, there is an extra configuration option for Ceph Dashboard, which can be used to configure the URL for accessing Grafana by the user's browser. This value will never be altered by cephadm. To set this configuration option, issue the following command:: $ ceph dashboard set-grafana-frontend-api-url It may take a minute or two for services to be deployed. Once completed, you should see something like this from ``ceph orch ls`` .. code-block:: console $ ceph orch ls NAME RUNNING REFRESHED IMAGE NAME IMAGE ID SPEC alertmanager 1/1 6s ago docker.io/prom/alertmanager:latest 0881eb8f169f present crash 2/2 6s ago docker.io/ceph/daemon-base:latest-master-devel mix present grafana 1/1 0s ago docker.io/pcuzner/ceph-grafana-el8:latest f77afcf0bcf6 absent node-exporter 2/2 6s ago docker.io/prom/node-exporter:latest e5a616e4b9cf present prometheus 1/1 6s ago docker.io/prom/prometheus:latest e935122ab143 present Configuring SSL/TLS for Grafana ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ``cephadm`` deploys Grafana using the certificate defined in the ceph key/value store. If no certificate is specified, ``cephadm`` generates a self-signed certificate during the deployment of the Grafana service. A custom certificate can be configured using the following commands: .. prompt:: bash # ceph config-key set mgr/cephadm/grafana_key -i $PWD/key.pem ceph config-key set mgr/cephadm/grafana_crt -i $PWD/certificate.pem If you have already deployed Grafana, run ``reconfig`` on the service to update its configuration: .. prompt:: bash # ceph orch reconfig grafana The ``reconfig`` command also sets the proper URL for Ceph Dashboard. Using custom images ~~~~~~~~~~~~~~~~~~~ It is possible to install or upgrade monitoring components based on other images. To do so, the name of the image to be used needs to be stored in the configuration first. The following configuration options are available. - ``container_image_prometheus`` - ``container_image_grafana`` - ``container_image_alertmanager`` - ``container_image_node_exporter`` Custom images can be set with the ``ceph config`` command .. code-block:: bash ceph config set mgr mgr/cephadm/ For example .. code-block:: bash ceph config set mgr mgr/cephadm/container_image_prometheus prom/prometheus:v1.4.1 .. note:: By setting a custom image, the default value will be overridden (but not overwritten). The default value changes when updates become available. By setting a custom image, you will not be able to update the component you have set the custom image for automatically. You will need to manually update the configuration (image name and tag) to be able to install updates. If you choose to go with the recommendations instead, you can reset the custom image you have set before. After that, the default value will be used again. Use ``ceph config rm`` to reset the configuration option .. code-block:: bash ceph config rm mgr mgr/cephadm/ For example .. code-block:: bash ceph config rm mgr mgr/cephadm/container_image_prometheus Using custom configuration files ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ By overriding cephadm templates, it is possible to completely customize the configuration files for monitoring services. Internally, cephadm already uses `Jinja2 `_ templates to generate the configuration files for all monitoring components. To be able to customize the configuration of Prometheus, Grafana or the Alertmanager it is possible to store a Jinja2 template for each service that will be used for configuration generation instead. This template will be evaluated every time a service of that kind is deployed or reconfigured. That way, the custom configuration is preserved and automatically applied on future deployments of these services. .. note:: The configuration of the custom template is also preserved when the default configuration of cephadm changes. If the updated configuration is to be used, the custom template needs to be migrated *manually*. Option names """""""""""" The following templates for files that will be generated by cephadm can be overridden. These are the names to be used when storing with ``ceph config-key set``: - ``services/alertmanager/alertmanager.yml`` - ``services/grafana/ceph-dashboard.yml`` - ``services/grafana/grafana.ini`` - ``services/prometheus/prometheus.yml`` You can look up the file templates that are currently used by cephadm in ``src/pybind/mgr/cephadm/templates``: - ``services/alertmanager/alertmanager.yml.j2`` - ``services/grafana/ceph-dashboard.yml.j2`` - ``services/grafana/grafana.ini.j2`` - ``services/prometheus/prometheus.yml.j2`` Usage """"" The following command applies a single line value: .. code-block:: bash ceph config-key set mgr/cephadm/ To set contents of files as template use the ``-i`` argument: .. code-block:: bash ceph config-key set mgr/cephadm/ -i $PWD/ .. note:: When using files as input to ``config-key`` an absolute path to the file must be used. Then the configuration file for the service needs to be recreated. This is done using `reconfig`. For more details see the following example. Example """"""" .. code-block:: bash # set the contents of ./prometheus.yml.j2 as template ceph config-key set mgr/cephadm/services/prometheus/prometheus.yml \ -i $PWD/prometheus.yml.j2 # reconfig the prometheus service ceph orch reconfig prometheus Disabling monitoring -------------------- To disable monitoring and remove the software that supports it, run the following commands: .. code-block:: console $ ceph orch rm grafana $ ceph orch rm prometheus --force # this will delete metrics data collected so far $ ceph orch rm node-exporter $ ceph orch rm alertmanager $ ceph mgr module disable prometheus Deploying monitoring manually ----------------------------- If you have an existing prometheus monitoring infrastructure, or would like to manage it yourself, you need to configure it to integrate with your Ceph cluster. * Enable the prometheus module in the ceph-mgr daemon .. code-block:: bash ceph mgr module enable prometheus By default, ceph-mgr presents prometheus metrics on port 9283 on each host running a ceph-mgr daemon. Configure prometheus to scrape these. * To enable the dashboard's prometheus-based alerting, see :ref:`dashboard-alerting`. * To enable dashboard integration with Grafana, see :ref:`dashboard-grafana`. Enabling RBD-Image monitoring --------------------------------- Due to performance reasons, monitoring of RBD images is disabled by default. For more information please see :ref:`prometheus-rbd-io-statistics`. If disabled, the overview and details dashboards will stay empty in Grafana and the metrics will not be visible in Prometheus.